Electric switch



A g. 27, 1957 H. v. ELLIOTT ETAL 2,804,512

ELECTRIC SWITCH Filed NOV. 17, 1954 IN V EN TOR.

THEIR ATTORNEY United States Patent ELECTRIC swrrcn Harold V. Elliott and William E. Brown, Anderson, ImL, assignors to General Motors (Iorporation, Detroit, Mich., a corporation of Delaware Application November 17, 1954, Serial No. 469,346

3 Claims. (Cl. 200-41) This invention relates to electric switches and is particularly concerned with improvements in a switch wherein the reciprocal movement of a plunger causes rotary movement of a contact bridging member.

Switches of the plunger type as contemplated by the present invention have enjoyed wide acceptance when used as foot dimmer switches in automobiles. In this environment they are used to control the headlamp circuits to alternately provide high or low beams each time the plunger is depressed and a contact bridging member is rotated thereby in a step-by-step movement. The type of switch with which this invention is concerned is clearly set forth in a patent to William Earl Brown, Patent No. 2,496,118, which has been assigned to the assignee of the present invention. The switch according to the present invention represents an improvement over the switch disclosed in the aforementioned patent. This switch, because of the construction of its various parts, will permit a wider deviation in manufacturing tolerances and thus is easier to assemble and will have a longer trouble-free life as all possibility of engagement between the driving member and the stationary contacts is eliminated and prevents short circuits in the headlamp circuits.

It is an object therefore of the present invention to eliminate the possibilities of short circuits in the headlight circuits of a vehicle by providing a foot dimmer switch mechanism wherein a driving lug is located on. a driving member is constantly prevented from engagement with the stationary contacts of the switch by a wall of insulating material.

It is a further object of the present invention to provide a switch which is characterized by simplicity of construction, the economy in cost of manufacture and the reliability of operation.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred embodiment of the present invention is clearly shown.

In the drawings:

Figure l is a plan view of a switch embodying the present invention.

Figure 2 is a sectional view along line 2-2 in Figure 1.

Figure 3 is a view of a driving and driven means taken in the direction of arrow 3-3 along line 33 in Figure 2.

In the drawings the numeral 20 designates a switch casing or housing having an upwardly extending sleeve 21, a partition 22, and a housing 23 having an open side closed by a closure or block 24 of insulating material. The open side of the housing is recessed to provide a peripheral shoulder 25 and a peripheral flange 26. The closure is held against the shoulder by deforming the flange 26 at several places against the outer surfaces of the closure.

The bottom wall 27 and the closure 24 are each provided with suitably located recesses in direct alignment with each other to support a rod or shaft 28. The shaft loosely supports the driving or ratchet wheel 30 stamped from sheet metal.

A plunger 32, stamped from heavy sheet metal has an end 33 which is suitably formed to pass adjacent to shaft 28' and be guided by a lug, not shown, formed in the Wall 27. The plunger also has an extending portion 34 which passes through an aperture 35 in partition 22. This aperture 35 is complementary to the contour of the extending portion 34 and assists in guiding the plunger 32. in a straight line movement. The end portion 33 of the plunger 32 is provided with a projection, not shown, which is adapted to be received in any one of a plurality of equally spaced openings in the driving wheel so as to provide a ratchet connection therewith and rotate the wheel 3% in a step-by-step rotation when the plunger 33 is reciprocally moved as is clearly set forth in the Brown patent, supra.

The wheel 30 is provided with a tongue 36 which is preferably shaped as shown in Figure 3 so that it may be received in a socket 38 as defined by the spaced lugs Miami 42 which are interconnected by an intermediate portion 44 as formed on the carrier 46 which is formed of non-conducting material and loosely supported so as to be rotatable on shaft 28. The tongue 36 drives the carrier as about shaft 28. The face 47 of carrier 46 which is adjacent the closure 24 supports a bridging member 48. This member 43 is adapted to selectively engage certain of the spaced contacts 56 and because of its configuration, as described in the patent, supra, will provide a yieldable holding means against rotation of the various rotatable parts of the switch. A coil spring 52 surrounding rod 28 and disposed between the carrier 46 and the wheel 30 forces the bridging member 48 into engagement with the spaced contacts 5% and the wheel 30 into engagement with the plunger 33. This coil spring will permit the parts to move longitudinally along rod 28 and permit the parts to move in a step-by-step rotational movement when the plunger 32 is depressed. The present invention is particularly directed to an improvement in the switch as described in the patent, supra, and provides a wall between the extending lug 36 and any one of the stationary contacts 50. The wall which consists of the intermediate portion 44 of socket 38 prevents the extending lug 36 from passing beyond the face 47 of carrier 46 and from engagement with any one of the spaced contacts 50 when the switch is actuated. If this intermediate portion 44 is not present, the wheel 36 may inadvertently move against the force of spring 52 beyond face 47 and engage one of the contacts 50 so that a circuit is made between the battery terminal 54 which is connected with one of the contacts (it) and the ground, not shown, to which the body of the switch is connected.

This arrangement of providing a socket 338 for the extending shaped lug 36 is very desirable in that it provides for a switch structure that is easier to assemble as the lugs 40 and 42 will embrace the extending lug 36 and maintain the parts in relative position to one another during assembly.

While the embodiments of the present invention as herein disclosed, constitute preferred forms, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. In combination; a casing, a closure for the casing carrying a series of stationary contacts arranged in a circular row, a rod within the casing having one end supported in the casing and the other supported in the closure, a manually operated plunger extending through an opening in said casing and slidably supported thereby for movement perpendicular to the axis of the rod, an actuator rotatably supported on the rod, a ratchet means between said plunger and actuator for moving said actuator in one direction of rotation only upon reciprocal movements of said plunger, a disc axial and rotatory movements on the rod, a bridging member carried by said carrier adapted to selectively engage certain of said contacts, a spring means disposed between the actuator and carrier for urging the actuator against the plunger for maintaining the ratchet means effective, means on said bridging member for yieldably holding the actuator in any one of its actuated positions, and a means between said actuator and carrier for driving the carrier whereby the carrier rotates with said actuator at all times, said means including; a lug on the periphery of said actuator and a pair of lugs spaced on the periphery of said carrier having an intermediate web portion therebetween, said pairs of lugs being spaced to tightly embrace the lug on said actuator for forming said driving connections and said intermediate web portion being disposed for constantly preventing engagement between the lug of said actuator and the stationary contacts.

2. In a switch of the character described, having; a casing, a closure for the casing carrying stationary contacts, a stud supported by the casing and closure, a manuarlly operated actuator slidably supported by the casing perpendicular to the axis of the stud, said actuator having an end in said casing and disposed to pass adjacent said stud and engage a lug formed on said casing for guiding the actuator in straight line movements, a disc rotatably supported on the stud, a ratchet between said actuator and disc consisting of a pawl on the end of said actuator and openings in said disc wherein said pawl extends for moving the disc in one direction of rotation only upon reciprocal movements of said actuator, a disc shaped carrier mounted for axial and rotatory movements on the stud and carrying a bridging member adjacent the stationary contacts, spring means disposed between the carrier and disc tending to urge them apart and maintain said ratchet effective, and means on said bridging member for yieldably holding the actuator in any one of its actuated positions, the improvement comprising; a shaped lug projecting from the periphery of one side of said disc toward said carrier and a pair of lugs spaced on the periphery of said carrier defining a socket wherein the lug of said disc is tightly received for forming a driving connection between said carrier and disc and for preventing any engagement between the lug on said disc and said stationary contacts.

3. In combination; a casing, a closure for the casing shaped carrier mounted for carrying a series of stationary contacts arranged in a circular row, a rod within the casing having one end supported in the casing and the other supported in the closure, a manually operated plunger extending through an opening in said casing and slidably supported thereby for movement perpendicular to the axis of the rod, a lug in said casing for guiding the perpendicular movements of said plunger, an end on said plunger disposed within said casing and adapted to pass said rod and engage said lug during the reciprocal movements of said plunger, a disc like actuator rotatably supported on the rod, a ratchet means between said plunger and actuator, said ratchet means consisting of a series of openings arranged in a circular row on said actuator and a pawl on said end of the plunger adapted to extend into said openings for moving said actuator in one direction of rotation only upon reciprocal movements of said plunger, a disc shaped carrier of molded insulating material mounted for axial and rotatory movements on the stud, a bridging member non-rotatably mounted on said carrier and adapted to selectively engage certain of said contacts, a coiled spring disposed between the actuator and carrier for urging the bridging member in engagement with said contacts and the actuator against the plunger for maintaining the ratchet means eifective, means on said bridging member for yieldably holding the actuator in any one of its actuated positions, and a means between said actuator and carrier for driving the carrier whereby the carrier rotates with said actuator at all times, said second mentioned means including; a lug on the periphery of said actuator and a pair of spaced lugs integrally molded on the periphery of said carrier having an intermediate web portion disposed therebetween, said pairs of lugs being spaced to tightly embrace the lug on said actuator for forming said driving connection and said intermediate web portion being disposed for constantly preventing engagement between the lug of said actuator and the stationary contacts.

References Cited in the file of this patent UNITED STATES PATENTS 1,924,776 Flanders et a1 Aug. 29, 1933 2,231,387 Jones Feb. 11, 1941 2,291,993 Taubner Aug. 4, 1942 2,496,118 Brown Jan. 13, 1950 

